[PATCH 2/2] vinyl: apply box.cfg.snap_io_rate_limit to dump/compaction

[Vladimir Davydov]

On Fri, Jun 01, 2018 at 08:56:28PM +0300, Konstantin Osipov wrote:
> * Vladimir Davydov <vdavydov.dev at gmail.com> [18/05/29 18:20]:
> 
> > diff --git a/test/vinyl/snap_io_rate.test.lua b/test/vinyl/snap_io_rate.test.lua
> > new file mode 100644
> > index 00000000..836bf537
> > --- /dev/null
> > +++ b/test/vinyl/snap_io_rate.test.lua
> > @@ -0,0 +1,38 @@
> > +fiber = require('fiber')
> > +digest = require('digest')
> > +test_run = require('test_run').new()
> > +
> > +MB = 1024 * 1024
> > +TUPLE_SIZE = 1024
> > +TUPLE_COUNT = 100
> 
> This test runs for 3.8 seconds on my laptop.
> 
> You only need to run it for 0.2 seconds, definitely 1 second to
> test the rate.

xlog_write() throttles after writing a file for one second. So in order
to make sure throttling works as expected, we need to run a test for a
few seconds. To speed up the test, we need to rewrite the way throttling
works, but I don't think it's worth it.

> 
> Sorry for being painfully finicky about this, but I run tests
> every day.
> 
> If you hate this request, don't bother, this is a standalone test
> and can run in parallel.

Exactly.